Lumo by Proton review: In a world dominated by AI assistants like ChatGPT, Google Gemini, and Microsoft Copilot, privacy has become a critical concern. These tools often collect data, log conversations, and use inputs for training, raising serious risks for personal and sensitive information. That’s where Lumo by Proton shines as the privacy-first AI assistant that users have long awaited.
Launched in July 2025 by the trusted team behind Proton Mail, VPN, and Drive (with over 100 million users), Lumo extends Proton’s commitment to encryption and no-logs policies into the AI space. Accessible at lumo.proton.me with iOS and Android apps, it’s designed for everyday tasks while keeping your data completely confidential.
What Is Lumo by Proton?
Lumo is a conversational AI assistant designed to handle everyday tasks like answering questions, summarizing documents, writing emails, generating code, translating text, and even planning trips—all while prioritizing user privacy. Available as a web app at lumo.proton.me, with dedicated mobile apps for iOS and Android.
Unlike mainstream AI tools backed by Big Tech, Lumo is built on open-source large language models hosted in Proton’s secure infrastructure. This ensures no reliance on third-party providers like OpenAI, and crucially, your conversations are never used to train models or shared with advertisers.
Proton positions Lumo as “AI that works for you, not the other way around,” emphasizing zero-access encryption, no logs, and full transparency through open-source code.
Standout Privacy Features: Why Lumo Shines for Privacy Enthusiasts
Privacy is Lumo’s core selling point, and it delivers in ways that competitors simply don’t:
- Zero-Access Encryption: Saved chat histories are end-to-end encrypted and decryptable only on your device. Even Proton can’t access them.
No Logging or Training: Conversations aren’t stored server-side or used for model improvement. Ghost Mode: For ultimate anonymity, enable this to make chats disappear permanently upon closing the session. Open-Source Transparency: The code is fully auditable, allowing independent verification of privacy claims.
- European Jurisdiction: Based in privacy-friendly Switzerland/Europe, Lumo benefits from strong GDPR protections.
- Optional Web Search: Turned off by default to minimize data exposure.
Additional perks include secure file uploads (with integration to Proton Drive for encrypted files) and no mandatory account for basic use—perfect for quick, anonymous queries. European Jurisdiction: Based in privacy-friendly Switzerland/Europe, Lumo benefits from strong GDPR protections.
Optional Web Search: Turned off by default to minimize data exposure.
Additional perks include secure file uploads (with integration to Proton Drive for encrypted files) and no mandatory account for basic use—perfect for quick, anonymous queries.
In short, Lumo addresses the biggest AI privacy pitfalls head-on, making it ideal for sensitive topics like health advice, business strategies, or personal finances.
Performance and Capabilities: How Does It Stack Up?
Lumo isn’t just about privacy; it’s a capable assistant. Updates like Lumo 1.1 (August 2025) brought significant improvements in reasoning and speed, with 1.2 adding customization and dark mode.
Key features include:
- Document analysis and summarization
- Code generation and debugging
- Email drafting and rewriting
- Translation and explanations
- Task automation and brainstorming
It supports multiple languages and routes queries to specialized models.
While it matches many capabilities for everyday use, some users note it may not always lead in the most complex tasks compared to rapidly evolving rivals. However, for privacy-focused users, the trade-off is worthwhile.
Pricing and Plans: Accessible Yet Premium
Lumo offers tiered access:
- Guest Mode: Free, no account required, limited prompts.
- Free Plan: With a Proton account; adds features like an encrypted history.
- Lumo Plus: Paid subscription for unlimited chats, faster responses, and advanced features.
There’s also a business version for teams.
Pros and Cons
Pros:
- Unmatched privacy and security
- Open-source and transparent
- Clean interface with mobile apps
- Integrates with the Proton ecosystem
- Regular updates
Cons:
- Limits on free tier
- May lag in some advanced features
- Standalone subscription for full access
Final Verdict: A Game-Changer for Privacy-Conscious Users
Lumo by Proton lives up to its hype as the AI tool privacy lovers have been waiting for. In a world where AI innovation often comes at the expense of personal data, Lumo proves you don’t have to choose between powerful assistance and protection.
If privacy is your top priority, give Lumo a try today—it’s free to start at lumo.proton.me.
Last updated: December 2025. Features based on the latest releases.
